[llvm] [LV] Use VPReductionRecipe for partial reductions (PR #147513)

[Sam Tebbs via llvm-commits]

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@@ -2333,32 +2332,35 @@ class VPReductionPHIRecipe : public VPHeaderPHIRecipe,
   /// The recurrence kind of the reduction.
   const RecurKind Kind;
 
-  /// The phi is part of an in-loop reduction.
-  bool IsInLoop;
-
   /// The phi is part of an ordered reduction. Requires IsInLoop to be true.
   bool IsOrdered;
 
-  /// When expanding the reduction PHI, the plan's VF element count is divided
-  /// by this factor to form the reduction phi's VF.
-  unsigned VFScaleFactor = 1;
+  /// The scaling factor, relative to the VF, that this recipe's output is
+  /// divided by.
+  /// For outer-loop reductions this is equal to 1.
+  /// For in-loop reductions this is equal to 0, to specify that this is equal
+  /// to the VF (which may not be known yet). For partial-reductions this is
+  /// equal to another scalar value.
+  unsigned VFScaleFactor;
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SamTebbs33 wrote:

Done, thanks for the suggestion!

https://github.com/llvm/llvm-project/pull/147513